internal static void ProcessRequestInternal(HttpContext context, string pathOverride)
{
HttpRequest request = context.Request;
HttpResponse response = context.Response;
string virtualPathWithPathInfo;
string physicalPath;
FileInfo fileInfo;
long fileLength;
DateTime lastModifiedInUtc;
string etag;
string rangeHeader;
// custom virtual path providers that don't yeild a MapPathBasedVirtualFile
// are a special case, and do not support TransmitFile, WriteFile, Range requests,
// or the cache policy that we apply below
/*
* if (ProcessRequestForNonMapPathBasedVirtualFile(request, response, overrideVirtualPath)) {
* return;
* }
*
* if (overrideVirtualPath == null)
* {
* virtualPathWithPathInfo = request.Path;
* physicalPath = request.PhysicalPath;
* }
* else {
* virtualPathWithPathInfo = overrideVirtualPath;
* physicalPath = request.MapPath(overrideVirtualPath);
* }
*/
if (pathOverride != null)
{
physicalPath = pathOverride;
}
else
{
physicalPath = context.Request.PhysicalPath;
}
// Debug.Trace("StaticFileHandler", "Path= " + virtualPathWithPathInfo + ", PhysicalPath= " + physicalPath);
try
{
fileInfo = GetFileInfo(physicalPath);
}
catch (HttpException hex)
{
int httpCode = hex.GetHttpCode();
string httpError = String.Format("{0} ({1})", hex.Message, physicalPath);
throw new HttpException(httpCode, httpError, hex);
}
// Determine Last Modified Time. We might need it soon
// if we encounter a Range: and If-Range header
// Using UTC time to avoid daylight savings time bug 83230
lastModifiedInUtc = new DateTime(fileInfo.LastWriteTimeUtc.Year,
fileInfo.LastWriteTimeUtc.Month,
fileInfo.LastWriteTimeUtc.Day,
fileInfo.LastWriteTimeUtc.Hour,
fileInfo.LastWriteTimeUtc.Minute,
fileInfo.LastWriteTimeUtc.Second,
0,
DateTimeKind.Utc);
// Because we can't set a "Last-Modified" header to any time
// in the future, check the last modified time and set it to
// DateTime.Now if it's in the future.
// This is to fix VSWhidbey #402323
DateTime utcNow = DateTime.UtcNow;
if (lastModifiedInUtc > utcNow)
{
// use 1 second resolution
lastModifiedInUtc = new DateTime(utcNow.Ticks - (utcNow.Ticks % TimeSpan.TicksPerSecond), DateTimeKind.Utc);
}
etag = GenerateETag(lastModifiedInUtc, utcNow);
fileLength = fileInfo.Length;
// is this a Range request?
rangeHeader = request.Headers["Range"];
if (rangeHeader != null && rangeHeader.StartsWith("bytes", StringComparison.OrdinalIgnoreCase) &&
ProcessRangeRequest(context, physicalPath, fileLength, rangeHeader, etag, lastModifiedInUtc))
{
return;
}
// if we get this far, we're sending the entire file
SendFile(physicalPath, 0, fileLength, fileLength, context);
// Specify content type. Use extension to do the mapping
response.ContentType = MimeMapping.GetMapping(physicalPath);
// Static file handler supports byte ranges
response.AppendHeader("Accept-Ranges", "bytes");
// We want to flush cache entry when static file has changed
response.AddFileDependency(physicalPath);
/*
* NOTE: This was the code originally in the handler:
* // Set an expires in the future.
* response.Cache.SetExpires(utcNow.AddMinutes(5));
* // always set Last-Modified
* response.Cache.SetLastModified(lastModifiedInUtc);
* // always set ETag
* response.Cache.SetETag(etag);
* // always set Cache-Control to public
* response.Cache.SetCacheability(HttpCacheability.ServerAndPrivate);
*/
// set cache headers
HttpCachePolicy cachePolicy = response.Cache;
SetCachingPolicy(cachePolicy);
// set cache file info
cachePolicy.SetETag(etag);
cachePolicy.SetLastModified(lastModifiedInUtc);
}
internal static bool ProcessRangeRequest(HttpContext context,
string physicalPath,
long fileLength,
string rangeHeader,
string etag,
DateTime lastModified)
{
HttpRequest request = context.Request;
HttpResponse response = context.Response;
bool handled = false;
// return "416 Requested range not satisfiable" if the file length is zero.
if (fileLength <= 0)
{
SendRangeNotSatisfiable(response, fileLength);
handled = true;
return(handled);
}
string ifRangeHeader = request.Headers["If-Range"];
if (ifRangeHeader != null && ifRangeHeader.Length > 1)
{
// Is this an ETag or a Date? We only need to check two
// characters; an ETag either begins with W/ or it is quoted.
if (ifRangeHeader[0] == '"')
{
// it's a strong ETag
if (ifRangeHeader != etag)
{
// the etags do not match, and we will therefore return the entire response
return(handled);
}
}
else if (ifRangeHeader[0] == 'W' && ifRangeHeader[1] == '/')
{
// it's a weak ETag, and is therefore not usable for sub-range retrieval and
// we will return the entire response
return(handled);
}
else
{
// It's a date. If it is greater than or equal to the last-write time of the file, we can send the range.
if (IsOutDated(ifRangeHeader, lastModified))
{
return(handled);
}
}
}
// the expected format is "bytes = <range1>[, <range2>, ...]"
// where <range> is "<first_byte_pos>-[<last_byte_pos>]" or "-<last_n_bytes>".
int indexOfEquals = rangeHeader.IndexOf('=');
if (indexOfEquals == -1 || indexOfEquals == rangeHeader.Length - 1)
{
//invalid syntax
return(handled);
}
// iterate through the byte ranges and write each satisfiable range to the response
int startIndex = indexOfEquals + 1;
bool isRangeHeaderSyntacticallyValid = true;
long offset;
long length;
bool isSatisfiable;
bool exceededMax = false;
ByteRange[] byteRanges = null;
int byteRangesCount = 0;
long totalBytes = 0;
while (startIndex < rangeHeader.Length && isRangeHeaderSyntacticallyValid)
{
isRangeHeaderSyntacticallyValid = GetNextRange(rangeHeader, ref startIndex, fileLength, out offset, out length, out isSatisfiable);
if (!isRangeHeaderSyntacticallyValid)
{
break;
}
if (!isSatisfiable)
{
continue;
}
if (byteRanges == null)
{
byteRanges = new ByteRange[16];
}
if (byteRangesCount >= byteRanges.Length)
{
// grow byteRanges array
ByteRange[] buffer = new ByteRange[byteRanges.Length * 2];
int byteCount = byteRanges.Length * Marshal.SizeOf(byteRanges[0]);
Buffer.BlockCopy(byteRanges, 0, buffer, 0, byteCount);
/*unsafe {
* fixed (ByteRange * src = byteRanges, dst = buffer) {
* StringUtil.memcpyimpl((byte*)src, (byte*)dst, byteCount);
* }
* }
*/
byteRanges = buffer;
}
byteRanges[byteRangesCount].Offset = offset;
byteRanges[byteRangesCount].Length = length;
byteRangesCount++;
// IIS imposes this limitation too, and sends "400 Bad Request" if exceeded
totalBytes += length;
if (totalBytes > fileLength * MAX_RANGE_ALLOWED)
{
exceededMax = true;
break;
}
}
if (!isRangeHeaderSyntacticallyValid)
{
return(handled);
}
if (exceededMax)
{
SendBadRequest(response);
handled = true;
return(handled);
}
if (byteRangesCount == 0)
{
// we parsed the Range header and found no satisfiable byte ranges, so return "416 Requested Range Not Satisfiable"
SendRangeNotSatisfiable(response, fileLength);
handled = true;
return(handled);
}
string contentType = MimeMapping.GetMapping(physicalPath);
if (byteRangesCount == 1)
{
offset = byteRanges[0].Offset;
length = byteRanges[0].Length;
response.ContentType = contentType;
string contentRange = String.Format(CultureInfo.InvariantCulture, CONTENT_RANGE_FORMAT, offset, offset + length - 1, fileLength);
response.AppendHeader("Content-Range", contentRange);
SendFile(physicalPath, offset, length, fileLength, context);
}
else
{
response.ContentType = MULTIPART_CONTENT_TYPE;
string contentRange;
string partialContentType = "Content-Type: " + contentType + "\r\n";
for (int i = 0; i < byteRangesCount; i++)
{
offset = byteRanges[i].Offset;
length = byteRanges[i].Length;
response.Write(MULTIPART_RANGE_DELIMITER);
response.Write(partialContentType);
response.Write("Content-Range: ");
contentRange = String.Format(CultureInfo.InvariantCulture, CONTENT_RANGE_FORMAT, offset, offset + length - 1, fileLength);
response.Write(contentRange);
response.Write("\r\n\r\n");
SendFile(physicalPath, offset, length, fileLength, context);
response.Write("\r\n");
}
response.Write(MULTIPART_RANGE_END);
}
// if we make it here, we're sending a "206 Partial Content" status
response.StatusCode = 206;
response.AppendHeader("Last-Modified", FormatHttpDateTime(lastModified));
response.AppendHeader("Accept-Ranges", "bytes");
response.AppendHeader("ETag", etag);
response.AppendHeader("Cache-Control", "private");
handled = true;
return(handled);
}